graph G {
A -- B [label="1"];
A -- C [label="1"];
A -- D [label="1"];
A -- G [label="1"];
B -- C [label="2"];
B -- E [label="2"];
C -- G [label="3"];
C -- F [label="3"];
C -- D [label="3"];
D -- F [label="3"];
D -- E [label="3"];
D -- H [label="3"];
D -- G [label="3"];
E -- F [label="3"];
F -- G [label="3"];
F -- H [label="3"];
I -- K [label="3"];
I -- J [label="3"];
K -- L [label="3"];
J -- L [label="3"];
J -- M [label="3"];
L -- M [label="3"];
}